The invention concerns a safety device.
Such safety devices comprise a safety switch and an actuator arranged movably relative to the safety switch. The safety device thusly embodied is generally used in the sphere of safety technology. An example of such a use is an access security system for a hazardous area to which access can be barred by means of a safety door. In this case, the actuator is typically arranged on the safety door, while the safety switch is arranged on a frame structure delimiting the access.
Known safety switches have an RFID system with a transponder integrated in the actuator and a reading unit integrated in the safety switch. By means of this RFID system, the locking position of the safety door can be controlled. Only when the door is in the locking position is the transponder in the actuator spatially assigned to the reading unit in the safety switch such that transponder signals of the transponder are received by the reading unit.
In addition, the safety door can be secured in its locking position by means of the safety device. For this purpose, the safety switch typically has a locking element in the form of a locking bolt which, when the safety door is in the locking position, can be moved into a receptacle, in particular a recess in the actuator, thus effecting locking of the safety door.
A problem in such safety devices can be that the actuator can be brought into a position in such a manner that, while the RFID system still signals a locking position of the safety door, the locking bolt is, however, released from the receptacle of the actuator. The safety switch then reports a locked state of the safety door despite the fact that this does not correspond to the actual conditions.